hightide vs tidal wave

hightide

noun
  • The point at which the sea level is at its highest during any given cycle 

  • A great festival. 

tidal wave

noun
  • A crest of ocean water resulting from tidal forces. 

  • A large, sudden, and disastrous wave of water caused by a tremendous disturbance in the ocean; a tsunami. (See Usage notes below.) 

  • A sudden and powerful surge. 

  • A large, sudden inundation of water from the storm surge, or waves of that surge; a sudden surge of river water. 

  • A large and sudden rise and fall in the tide. 

How often have the words hightide and tidal wave occurred in a corpus of books? (source: Google Ngram Viewer )